The invention relates to an apparatus for sorting objects, especially those of flat shape, such as periodicals, compact disks or the like. The apparatus includes a primary conveyor which has gaps and on which objects can be placed, a plurality of secondary conveyors which are disposed underneath the gaps, and a control system which causes the distribution of the objects to one of the secondary conveyors with the aid of image recognition.
The German Patent No. 39 20 417 A1 discloses a sorting unit for flat cuttings. It consists of three conveyor paths running in tandem. Between the first and the second, and the second and the third conveyor paths is disposed a sorting switch. The sorting switches have switch bodies in the form of an acute wedge shape which point against the direction of conveyance. If the wedge points to the adjacent conveyor path, the objects pass over it to the next one. If the wedge rises up, however, the objects drop onto a conveyor path running below it.
A disadvantage of this sorting unit is that the system consists of a plurality of individual running conveyor paths. The sorting switches between them can perform their function only when the conveyor path is substantially longer than the length of the objects to be sorted. Thus the apparatus is very long and complicated and any simple and properly positioned sorting of the objects is not permitted.
Another German Patent No. 36 04 562 A1 discloses a sorting apparatus which consists of a main conveyor and a plurality of sorting conveyors. A switch is disposed, at the point at which the sorting conveyors run from the main conveyor, which switch consists of rolls disposed side by side, which can be turned in and out and driven.
In order to be able nevertheless to distribute or sort objects the switch must be actuated so that the objects can be steered straight or turned left or right on an equal level.
In the U.S. Pat. No. 4,792,034 there is described a sorting apparatus which consists of a main conveyor and sorting conveyors in which switching rolls are disposed on a flap switch to the sorting conveyor. In order to steer an object from the main conveyor to the sorting conveyor, the flap switch, and with it the switching roll, must be switched, requiring a great amount of time and power, so that such a system is slow and suitable only for heavy objects.
The German Patent No. 37 17 736 discloses a transport system which consists of a covered belt run with conveyor belts which are guided over conveyor rolls. Between the transport belts are disposed switches which are controlled by a coding system.
To be able to sort objects, here again several conveyor belts and separate switches are necessary. Also, a system of this kind, which is designed for sorting letters, is not suitable for the sorting of magazines. Since individual magazines have to be placed upright in the transport system, they may open when they are turned out of the switches, so that their position changes and they cannot be deposited perfectly.
Magazines which could not be sold after their appearance date must be sent back to the particular publisher for credit. To do so, it is necessary to sort these magazines by title and publisher. It is known in this case to transport the magazines in line on a belt. Beside the belt, pushing systems are disposed at corresponding stations. If one of the magazines is recognized to be associated with one of the stations, the pusher moves across the belt and pushes the magazine off. It is disadvantageous in this case that, when the magazine is laterally pushed off, the magazine can be skewed or displaced by the continued running of the belt. Stacking in correct position and proper bundling is thus possible only with great difficulty. Furthermore, the running belt can be damaged or a pushing beyond the belt can be caused by the pushing system, leading to additional complications.